It’s not pee. It appears under my car in the winter because I can see it in the snow. No, it doesn’t smell like gas, and if I were leaking coolant at that rate I’d have had an issue long ago.

So wtf is the geeenish yellow under the car ?

UPDATE: Well, the internet is an amazing place, Oppo in particular I must say. See Wacko’s response in the comments for a link to a full explanation. But basically there’s a chemical reaction that occurs between the exhaust, heat shields, and salt-laden snow that creates this yellowish color.

I have been wondering this FOR YEARS and I will sleep better tonight. However, having never noticed any fluid level changes, I never really lost sleep over it, but this is so satisfying nonetheless. Cheers!